XRD1 Highlights

Carbonic Anhydrase

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Stereoview of the electron density map and corresponding models of HCAII active site in complex with (a) CO2 at 1.56 A resolution and (b) HCO3- at 1.66 A resolution. The bicarbonate has van der Walls contacts with the same residues as CO2.

Carbonic anhydrase, a zinc metalloenzyme, catalyzes the reversible hydration of carbon dioxide to bicarbonate. It is involved in processes connected with acid–base homeostasis, respiration, and photosynthesis. More than 100 distinct human carbonic anhydrase II (HCAII) 3D structures have been generated in last 3 decades [Liljas A, et al. (1972) Nat New Biol 235:131–137], but a structure of an HCAII in complex with CO2 or HCO3 has remained elusive.
Here, we report previously undescribed structures of

HCAII:CO2 and HCAII:HCO3 complexes, together with a 3D molecular film of the enzymatic reaction observed successively in the same crystal after extended exposure to X-ray.

Retieve Article


Structural study of X-ray induced activation of carbonic anhydrase; Sjöblom B., Polentarutti M. and Djinović-Carugo K., PNAS 106, 10609 (2009); doi:10.1073/pnas.0904184106


Ultima modifica il Mercoledì, 08 Settembre 2021 14:57